Florence work1

[cvvergara]

Fixes #209

• pumped up version to 2.8
• Argentina -> Firenze
• Adjusted the places ordering to have things making sense on the queries
• Found suitable points for chapter 8
• All images are updated
• Installation shows how to install ISO (OSGeoLive does not have those instructions, and the only available version is ISO while we develop workshop)
• Locale pot/en files updated (to be used with transifex)

@pgRouting/admins

[cvvergara]

Merged without a review, I have too much on my plate to be waiting for a review

[omshinde]

Hi @cvvergara.
My bad, I missed out on reviewing it on time...Will be on the lookout for the review notifications attentively. Thanks for your efforts. :)